Such a display system, which is installed in the cockpit, is intended in a conventional manner to provide the pilot or pilots of the aircraft with information (such as altitude, speed, attitude, navigation, engine speeds, status of systems, etc.) which is used by the pilot or pilots during a flight of the aircraft. Some of this information, for example short-term piloting information, is critically necessary for the pilot or pilots to fly the aircraft in complete safety.
Hence, a failure of a screen which displays an image containing information which is absolutely necessary for piloting gives rise to a serious safety problem for the aircraft. Specific search procedures are usually provided to allow the pilot to find at least some of the information lost by the failure. However, such search procedures involve a very heavy workload for the pilot, a workload which often appears excessive especially in flight phases (such as landing or take-off, for example) in which the operations of piloting the aircraft require the full attention of the pilot.